What are event types? What are they used for?
An event type is an identifier associated with an event input or an event output of a function block type, assigned as part of the event input or output declaration, as described in IEC 61499-1-2.2.1.1. It can be used by software tools to assure that event connections are not improperly mixed, for instance to assure that an event output that is intended to be used for initialization is not connected to an event input that is intended to be used for alarm processing. Event types cannot be detected by execution control charts (ECCs), so the type of an event cannot be used to influence the processing of events in basic function block types. IEC 61499 does not define any standard event types other than the default type EVENT. • Why and when should I use the WITH construct? When you are designing function block types, you use the WITH construct to specify: • which input variables to sample when an event occurs at the associated event input of an instance of the type; • which output variable
